'\" te
.\" Copyright (C) 2003, Sun Microsystems, Inc. All Rights Reserved
.\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.  See the License for the specific language governing permissions and limitations under the License.
.\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
.TH GSS_UNWRAP 3GSS "Jan 15, 2003"
.SH NAME
gss_unwrap \- verify a message with attached cryptographic message
.SH SYNOPSIS
.LP
.nf
\fBcc\fR [ \fIflag\fR... ] \fIfile\fR... \fB-lgss\fR  [ \fIlibrary\fR... ]
#include <gssapi/gssapi.h>

\fBOM_uint32\fR \fBgss_unwrap\fR(\fBOM_uint32 *\fR\fIminor_status\fR,
     \fBconst gss_ctx_id_t\fR \fIcontext_handle\fR,
     \fBconst gss_buffer_t\fR \fIinput_message_buffer\fR,
     \fBgss_buffer_t\fR \fIoutput_message_buffer\fR, \fBint *\fR\fIconf_state\fR,
     \fBgss_qop_t *\fR\fIqop_state\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBgss_unwrap()\fR function converts a message previously protected by
\fBgss_wrap\fR(3GSS) back to a usable form, verifying the embedded \fBMIC\fR.
The \fIconf_state\fR parameter indicates whether the message was encrypted; the
\fIqop_state\fR parameter indicates the strength of protection that was used to
provide the confidentiality and integrity services.
.sp
.LP
Since some application-level protocols may wish to use tokens emitted by
\fBgss_wrap\fR(3GSS) to provide secure framing, the \fBGSS-API\fR supports the
wrapping and unwrapping of zero-length messages.
.SH PARAMETERS
.sp
.LP
The parameter descriptions for \fBgss_unwrap()\fR follow:
.sp
.ne 2
.na
\fB\fIminor_status\fR\fR
.ad
.RS 25n
The status code returned by the underlying mechanism.
.RE

.sp
.ne 2
.na
\fB\fIcontext_handle\fR\fR
.ad
.RS 25n
Identifies the context on which the message arrived.
.RE

.sp
.ne 2
.na
\fB\fIinput_message_buffer\fR\fR
.ad
.RS 25n
The message to be protected.
.RE

.sp
.ne 2
.na
\fB\fIoutput_message_buffer\fR\fR
.ad
.RS 25n
The buffer to receive the unwrapped message. Storage associated with this
buffer must be freed by the application after use with a call to
\fBgss_release_buffer\fR(3GSS).
.RE

.sp
.ne 2
.na
\fB\fIconf_state\fR\fR
.ad
.RS 25n
If the value of \fIconf_state\fR is non-zero, then confidentiality and
integrity protection were used. If the value is zero, only integrity service
was used. Specify \fBNULL\fR if this parameter is not required.
.RE

.sp
.ne 2
.na
\fB\fIqop_state\fR\fR
.ad
.RS 25n
Specifies the quality of protection provided. Specify \fBNULL\fR if this
parameter is not required.
.RE

.SH ERRORS
.sp
.LP
\fBgss_unwrap()\fR may return the following status codes:
.sp
.ne 2
.na
\fB\fBGSS_S_COMPLETE\fR\fR
.ad
.RS 25n
Successful completion.
.RE

.sp
.ne 2
.na
\fB\fBGSS_S_DEFECTIVE_TOKEN\fR\fR
.ad
.RS 25n
The token failed consistency checks.
.RE

.sp
.ne 2
.na
\fB\fBGSS_S_BAD_SIG\fR\fR
.ad
.RS 25n
The \fBMIC\fR was incorrect.
.RE

.sp
.ne 2
.na
\fB\fBGSS_S_DUPLICATE_TOKEN\fR\fR
.ad
.RS 25n
The token was valid, and contained a correct \fBMIC\fR for the message, but it
had already been processed.
.RE

.sp
.ne 2
.na
\fB\fBGSS_S_OLD_TOKEN\fR\fR
.ad
.RS 25n
The token was valid, and contained a correct \fBMIC\fR for the message, but it
is too old to check for duplication.
.RE

.sp
.ne 2
.na
\fB\fBGSS_S_UNSEQ_TOKEN\fR\fR
.ad
.RS 25n
The token was valid, and contained a correct \fBMIC\fR for the message, but has
been verified out of sequence; a later token has already been received.
.RE

.sp
.ne 2
.na
\fB\fBGSS_S_GAP_TOKEN\fR\fR
.ad
.RS 25n
The token was valid, and contained a correct \fBMIC\fR for the message, but has
been verified out of sequence; an earlier expected token has not yet been
received.
.RE

.sp
.ne 2
.na
\fB\fBGSS_S_CONTEXT_EXPIRED\fR\fR
.ad
.RS 25n
The context has already expired.
.RE

.sp
.ne 2
.na
\fB\fBGSS_S_NO_CONTEXT\fR\fR
.ad
.RS 25n
The \fIcontext_handle\fR parameter did not identify a valid context.
.RE

.sp
.ne 2
.na
\fB\fBGSS_S_FAILURE\fR\fR
.ad
.RS 25n
The underlying mechanism detected an error for which no specific \fBGSS\fR
status code is defined.  The mechanism-specific status code reported by means
of the \fIminor_status\fR parameter details the error condition.
.RE

.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(7)  for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
MT-Level	Safe
.TE

.SH SEE ALSO
.sp
.LP
.BR gss_release_buffer (3GSS),
.BR gss_wrap (3GSS),
.BR attributes (7)
.sp
.LP
\fISolaris Security for Developers Guide\fR
